Ensuring the integrity of Working Ground Connection Points in Stations

Temporary protective grounding is crucially important for ensuring the safety of workers, the public and the protection of power system equipment. The proper connection of working grounds to the buried ground grid conductors is essential to safe working conditions in a substation. This report summarizes the key findings of technical standards and reports, as well industrial experiences on temporary protective grounding, compatibility between attachment points and clamps, and worker exposure voltage calculation methods. The study proposes maintenance and testing practices for attachment points and temporary protective grounds to ensure the integrity of working ground attachment points in stations. The best practices for ensuring the integrity of attachment points can be grouped into three general categories: a) Visual Integrity Inspection; b) Electrical IntegrityTesting; and c) Mechanical Connector Integrity Inspection. Reference resistance values for integrity testing are provided, along with the most optimal sensitive nodes of the grid to connect testing probes.